Fix log file and disable LSAN usage in sidecar (#602)

* Use hard libc::_exit to prevent side effects

Like leak sanitizer running here; we definitely do not have cleaned up anything at this point.

* Hard-disable LSAN in sidecar process

Signed-off-by: Bob Weinand <[email protected]>

* Explicitly disable log_method when it could not be opened

Signed-off-by: Bob Weinand <[email protected]>

---------

Signed-off-by: Bob Weinand <[email protected]>

sidecar/src/entry.rs

@@ -139,16 +139,12 @@ where
         .map_err(|e| e.into())
 }
 
-pub fn daemonize(listener: IpcServer, cfg: Config) -> anyhow::Result<()> {
+pub fn daemonize(listener: IpcServer, mut cfg: Config) -> anyhow::Result<()> {
     #[allow(unused_unsafe)] // the unix method is unsafe
     let mut spawn_cfg = unsafe { spawn_worker::SpawnWorker::new() };
 
     spawn_cfg.target(entrypoint!(ddog_daemon_entry_point));
 
-    for (env, val) in cfg.to_env().into_iter() {
-        spawn_cfg.append_env(env, val);
-    }
-
     match cfg.log_method {
         config::LogMethod::File(ref path) => {
             match File::options()
@@ -164,6 +160,7 @@ pub fn daemonize(listener: IpcServer, cfg: Config) -> anyhow::Result<()> {
                 }
                 Err(e) => {
                     tracing::warn!("Failed to open logfile for sidecar: {:?}", e);
+                    cfg.log_method = config::LogMethod::Disabled;
                     spawn_cfg.stdout(Stdio::Null);
                     spawn_cfg.stderr(Stdio::Null);
                 }
@@ -176,6 +173,11 @@ pub fn daemonize(listener: IpcServer, cfg: Config) -> anyhow::Result<()> {
         _ => {}
     }
 
+    for (env, val) in cfg.to_env().into_iter() {
+        spawn_cfg.append_env(env, val);
+    }
+    spawn_cfg.append_env("LSAN_OPTIONS", "detect_leaks=0");
+
     setup_daemon_process(listener, &mut spawn_cfg)?;
 
     let mut lib_deps = cfg.library_dependencies;

spawn_worker/src/unix/spawn.rs

@@ -634,8 +634,8 @@ impl SpawnWorker {
                 }
                 unsafe {
                     libc::close(skip_close_fd);
+                    libc::_exit(0);
                 }
-                std::process::exit(0);
             }
         }